The Slippery Slope of Embryonic Stem Cell Research

President Obama has reversed a restriction on federal funds for embryonic stem cell research (ESCR), placing America that much farther down the slippery slope that could eventually lead to the creation of new human life solely for the purpose of research and medical treatments. Though he did not directly order a change to the NIH guidelines set during Clinton’s administration banning the use of federal funds for embryo creation and the making of animal-human chimera embryos, it is telling that the only restriction he imposed was a ban on reproductive cloning; stated Pres. Obama, “we will ensure that our government never opens the door to the use of cloning for human reproduction.”

However, even if the NIH initially upholds the guidelines set during Clinton’s administration, if the purpose of ESCR is to eventually provide medical treatments, then a future reversal of the ban against embryo creation is inevitable. Why? For the same reason that people in need of organ transplants die even though organ donation is perfectly legal and there are plenty of available donors: the shortage of matching donor tissue. If a person needs a new organ, doctors cannot just transplant the organs from any dead body; the donor and the recipient must have a number of matching tissue characteristics – very rare between unrelated people – in order for the transplant to have any probability of success, and even then the patient must be pumped full of immunosuppresant drugs to keep the person’s own body from attacking or rejecting the transplanted organ or tissue.

This same problem will hinder treatments using ESCs. To develop a viable treatment, a doctor must use a stem cell line that has a significant degree of tissue correspondence to the person requiring treatment, otherwise the recipient’s immune system will simply destroy all the injected stem cells or tissue, because it considers it to be an outside invader. The critical question is, how many stem cell lines would be available without the creation of more embryos specifically for research?

Addressing the use of “leftover” embryos

One of the primary arguments of proponents of ESCR is that there are hundreds of thousands of frozen embryos, “leftovers” from IVF procedures, that would simply “go to waste” if they weren’t used for research. Why would anyone, the argument goes, be unwilling to allow these “leftover” embryos to be used to develop treatments that could possibly save millions of lives? This argument seems convincing even to those who in principle oppose ESCR on the grounds that human life is lost. If they will be discarded anyway, why not at least use them for some good? This is sometimes even viewed as a positive means to offset the tragedy of the loss of innocent life.

Let me address this argument in two ways: first by moral analogy and then mathematically.

Let’s say a family member is dying of heart failure, and requires a heart transplant to continue living. The hospital runs a search and comes up with a tissue match. The heart that could save your family member belongs to a convict who is now sitting on Death Row awaiting execution. Unfortunately, he isn’t scheduled to be executed for another couple years, by which time it would be too late for your family member.

The question is: would it be morally, legally, or ethically right for you to request that the prison reschedule the convict’s execution for the very next day so that you could obtain the man’s heart for your family member? Since the convict is going to die anyway, why not kill him now so that his death can actually serve some good? The answer of course, is because this would be WRONG! Even a convicted criminal, awaiting execution for committing a horrendous crime, and whose continued existence arguably serves no further benefit to society, even this person has the right for his life to not be ended before his time for the purpose of medical research. Who then can claim the right to end the life of an innocent unborn human? It will indeed be a great tragedy when these hundreds of thousands of frozen embryos eventually die or are discarded; what would be a greater tragedy is if we try to diminish the depth of this tragedy by trying to justify it with some demeaning purpose.

But if moral arguments don’t do it for you, then let’s do some math.

The most accurate data on the number of frozen embryos available has been collected by RAND researchers Gail L. Zellman and C. Christine Fair, together with the Society of Assisted Reproductive Technology (SART) Working Group led by David Hoffman. Their findings include (emphasis added):

  • Nearly 400,000 embryos (fertilized eggs that have developed for six or fewer days) have been frozen and stored since the late 1970s.
  • Patients have designated only 2.8 percent (about 11,000 embryos) for research. The vast majority of frozen embryos are designated for future attempts at pregnancy.
  • From those embryos designated for research, perhaps as many as 275 stem cell lines (cell cultures suitable for further development) could be created. The actual number is likely to be much lower.

The researchers explain why only 275 stem cell lines might be obtained even though 11,000 embryos are available for research:

Although the 11,000 embryos designated for research might seem like a large number, the actual number of embryos that might be converted into stem cell lines is likely to be substantially lower. Because assisted reproductive technology clinics generally transfer the best-quality embryos to the patient during treatment cycles, the remaining embryos available to be frozen are not always of the highest quality. (High-quality embryos are those that grow at normal rates.) In addition, some of the frozen embryos have been in storage for many years, and at the time that some of those embryos were created, laboratory cultures were not as conducive to preserving embryos as they are today. Some embryos would also be lost in the freeze-and-thaw process itself.

To illustrate how such laboratory conditions might limit the number of embryos available for research, the RAND-SART team performed a series of calculations. Drawing upon the few published studies in this area, they estimated that only about 65 percent of the approximately 11,000 embryos would survive the freeze-and-thaw process, resulting in 7,334 embryos. Of those, about 25 percent (1,834 embryos) would likely be able to survive the initial stages of development to the blastocyst stage (a blastocyst is an embryo that has developed for at least five days). Even fewer could be successfully converted into embryonic stem cell lines. For example, researchers at the University of Wisconsin needed 18 blastocysts to create five embryonic stem cell lines, while researchers at The Jones Institute used 40 blastocysts to create three lines.

Using a conservative estimate between the two conversion rates from blastocyst to stem cells noted above (27 percent and 7.5 percent), the research team calculated that about 275 embryonic stem cell lines could be created from the total number of embryos available for research. Even this number is probably an overestimate because it assumes that all the embryos designated for research in the United States would be used to create stem cell lines, which is highly unlikely.

Here is the key point: the figures of hundreds of thousands of frozen embryos that is tossed around by proponents of ESCR is meaningless, because only a tiny fraction of that number (11,000) would actually be available to research, and then only a small percentage of that number (275) might possibly yield a usable stem cell line. So instead of having hundreds of thousands of embryos to work with, researchers might in fact only obtain 275 stem cell lines.

A recent study has suggested that more couples may be willing to donate their embryos to research, resulting in perhaps 100,000 available embryos and “a potential 100-fold increase in the number of stem cell lines,” although the article didn’t explain how having 10 times the number of available embryos would result in a 100-fold increase in stem cell lines. This would then result in a maximum of 27,500 stem cell lines derived from “leftover” embryos. Many researchers would say that this is an overly optimistic number. According to Dr. Barry Behr of Stanford University, “By far, by far, the vast majority of embryos that are frozen are not good. If we thawed 10,000 embryos, we would get 100 or so that are viable blastocysts” (from Do No Harm).

But let’s grant this unreasonably high number for the sake of argument. Remember our earlier discussion on the critical importance of finding an exact tissue match before a stem cell treatment will be accepted by the recipient’s body? The Americans for Cures website states that: “Over 100 million Americans may benefit from stem cell therapies and cures.” Now what percentage of these 100,000,000 Americans may potentially find a match among the 27,500 potential stem cell lines derived from “leftover” embryos? Do the math!

Even if actual treatments using embryonic stem cells are developed in the near future, how long will it take before researchers run out of “leftover” embryos that are tissue matched to the waiting patients? And when they do reach this point—most likely sooner rather than later—will these researchers say, “Well, we’ve used up all the leftover embryos… I guess we can’t do any more treatments with embryonic stem cells anymore! Tough luck for those who didn’t get a match…” and then close up shop? Once the dike has been punctured, the flow of water will only increase, and the demand for more embryos for the purpose of medical research will only increase. And the only way to obtain more embryos is to actually create them specifically for the purpose of research.

This is currently already being done in privately funded labs around the world. The method of choice is Somatic Cell Nuclear Transfer (SCNT), sometimes given the benevolent sounding name “therapeutic cloning.” But the only difference between “therapeutic” cloning and reproductive cloning is that in the latter, the clone is allowed to live and be born, while in the former, the clone is destroyed in the process of acquiring the “therapy.” Even the clones on The Island were given the chance to live a little before they were taken off to be harvested for their body parts.

SCNT has its own ethical issues that will affect its potential success, including the very real potential that women would be exploited to harvest their eggs (see Hands Off Our Ovaries), which is required for SCNT. However, the key point that I want to make in this post is that “leftover” embryos from fertility treatments will not be enough for the purpose of developing actual treatments, and instead in the very near future we can expect to see tax-payer funding for the creation of embryos specifically for the purpose of research and medical treatments.

There has been a raging debate on the ethics of using tissue from aborted fetuses for transplant, because of the high likelihood that woman may be coerced into conceiving and aborting babies just so the body parts can be used (see this egregious story for example). This same thing—in essence—may soon occur on a massive scale if people continue to pursue treatments using embryonic stem cells.

Let me finish this entry with the response given by House Republican Leader John Boehner following  President Obama’s decision to allow taxpayer funding of human embryonic stem cell research:

“This decision runs counter to President Obama’s promise to be a president for all Americans.  For a third time in his young presidency, the President has rolled back important protections for innocent life, further dividing our nation at a time when we need greater unity to tackle the challenges before us.  I fully support stem cell research, but I draw the line at taxpayer-funded research that requires the destruction of human embryos, and millions of Americans feel similarly.  As we move forward, I am hopeful that the President will re-evaluate this and other controversial decisions that put government at odds with the sanctity of human life.

“Non-embryonic stem cell research is not only showing great promise in the laboratory, but its applications are already being used to treat scores of diseases and medical conditions.  Indeed, science and respect for human life can coexist.  Politicians in Washington would be well-served to recognize this fact before they ask taxpayers to subsidize the destruction of innocent human life simply to advance a particular agenda.  Instead of asking taxpayers to pay for efforts that destroy life, Congress and the Administration should support bipartisan solutions like Rep. Randy Forbes’ Patients First Act, which would promote stem cell research that is actually getting results.”

In the near future I hope to describe more on this promising non-embryonic stem cell research that Boehner describes.

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  1. Josh Wims said...

    Hey Mr.Yeh, this is Josh Wims and I feel that stem cell research is a great thing if it works, but I also believe that it is morally wrong to to take human embryos to use in order to carry out this process because many of those embryos are innocent humans that are living

  2. Kendalf said...

    Thank you for your comment, Josh. I think what many of us who oppose embryonic stem cell research are trying to help people understand is that you can have the advantages of stem cell research without the use of human embryos by pursuing the use of induced pluripotent stem cells (stem cells that come from "reprogramming" skin cells) and adult stem cells. It isn't a choice between either stem cell treatments or save embryos; the choice is between stem cell research that requires human embryos, or stem cell research that doesn't require human embryos.

  3. bob said...

    Mr. Yeh, its John Davis. What I wonder is why, if the options are there and researchers can use the "reprogramed" skin cells and adult stem cells, why aren't these options being investigated? If the answer is significantly less controversial, then why are we not exploring it more thoroughly, why is there a debate at all? Is there a drawback to using these other methods?

  4. Kendalf said...

    Hi John. The good news is that within the research community these options are certainly being investigated. Most of the exciting news recently from stem cells has been coming from research using iPSCs and adult stem cells. The majority of the stem cell research highlights on the NIH "Stem Cell Information" page from 2008 and so far in 2009 have all involved the use of iPSCs. So far, many of the initial concerns over the use of iPSCs have already been cleared up, such as the initial use of retroviruses to insert the genes, and the propensity of iPSCs to cause tumors.

    One of the primary arguments given by scientists for why ESCr should continue is that, at this point, we still don't know yet which line of research will actually obtain the best results, so we shouldn't shut down any particular line yet, even if one has shown more promise than the other. I will try to address this argument in a later entry.

    In the realm of public opinion, however, due to much misrepresentation by the media and celebrities confusing the issues, iPSCs have gotten much less positive publicity than they deserve. Though I have to say I was quite pleased that the Feb. 9, 2009 issue of TIME Magazine featured a cover story on iPSCs. So word is getting out, but a lot of confusion about stem cell research still needs to be cleared up.

    For a very real example of this, take a look at this Facebook debate that I've been engaged in the last few days. Unfortunately, I'm outnumbered 4 to 1, so I can't quite address every single point that is raised, but I feel that I have raised some valid issues and defended the reasons why we should not use embryos for research.

    It does make you wonder, if the ultimate purpose is to do good and find treatments for people, why there are those who take such a hard line against anyone who dares to bring any sense of morality or ethics into the discussion of embryonic stem cell research.

    Thanks for dropping by, and help me get the word out! I certainly welcome any other questions you may have!

  5. Mark Haugaard said...

    I've got a question. Why didn't Obama endorse the use of adult stem cell research? According to Focus on the Family, adult stem cells have cured over 70 diseases. But, there have been no successes so far with embryonic stem cell research.
    Obama says that the National Institutes of Health is supposed to make the guidelines for the responsible use of stem cells. But what do they consider responsible and who is going to decide what is responsible means? Is there going to be a Doctor Frankenstein deciding what to use the embryos for? Later when babies with deformities are born will they be killed because people will think of them as undeveloped?

  6. Mr. Hyde said...

    Mr. yeh, you wrote, "For the same reason that people in need of organ transplants die even though organ donation is perfectly legal and there are plenty of available donors: the shortage of matching donor tissue. If a person needs a new organ, doctors cannot just transplant the organs from any dead body; the donor and the recipient must have a number of matching tissue characteristics – very rare between unrelated people.

    This point was made by Dr. Oz on Oprah recently. He and Michael J. Fox were on discussing ESCR and he made it clear that the way research is turning is taking adult stem-cells from, for example, Michael J. Fox and using those to cure his disease--not embryonic stem-cells.

    I know you've been to my blog, but I posted about that issue and included a link for those who care to watch the clip of the Oprah show.

  7. Kendalf said...

    Hello Mr. Hyde,
    Thank you for that link. My wife also told me about that episode. It is certainly good to see that such a large audience is finally hearing what many of us have been saying all this time.

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